1. Field of the Invention
The invention concerns a cycle fixing device for a cycle rack and in particular for a so-called "upright" type cycle rack. The cycle in a cycle rack of this kind is held in a vertical position.
The invention also concerns a cycle rack including a fixing device of this kind.
2. Description of the Prior Art
In the context of the invention, the term cycle is to be understood in its widest sense: man's, woman's or child's bicycle, racing bike, "all terrain" bike (ATR), motorcycle, etc.
These cycle racks are usually employed to carry cycles on the roof or on the trunk of an automobile vehicle. They are fitted onto a roof rack or onto bars attached to the vehicle.
For simplicity, in the following description, the cycle rack will be referred to as a "bike rack", which is its usual name. Likewise, the various kinds of cycle are all referred to as "bikes".
Many types of bike rack are available on the market. Some require the wheels to be removed, but in most cases the fixing means do not require this.
The first bike racks to be introduced were such that the cycle was fixed by the saddle and the handlebars, upside down. Fixing the bike was somewhat complicated and time consuming.
In the last few years bike racks have been generally adopted in which the bike is fixed vertically, but in its natural position, i.e. the right way up.
Bike racks of this kind have one or more arms (usually two). The lower end of the fixed arm (or of each fixed arm) is fixed to a support and can usually pivot about an axis. The upper end (or each upper end) carries a jaw type member adapted to fit around a tube of the bike frame.
There are numerous designs of this kind, the most usual ones being as follows: large clamp, small articulated jaws or cam system.
With regard to the bikes themselves, the designs on offer are tending to diversify to meet ever more specific requirements. As a result the general shape of the bike frame varies from one type to another, as do the specifications of the tubes from which the frames are made. The diameter of the tubes (when they are cylindrical) or more generally their dimensions (when they are oblong in shape) vary significantly from one manufacturer to another, and possibly from one model to another from the same manufacturer.
A first problem that arises is that of adapting the fixing devices of bike racks to these various configurations. It is clear that embodiments which use a large clamp or a small jaw can accommodate only slight variations in the diameter of circular cross-section tubes around a mean value. Their application is in practise to circular cross-section tubes of small diameter, typically in the range 30 mm to 60 mm. Given also that oblong cross-section tubes usually have a low resistance to compression, it is equally clear that these embodiments are hardly suited to this type of tube. There would be a risk of distortion of the tube unless jaws or clamps were employed for a single size of tube, i.e. matching the exterior cross section of the tube. Cam systems offer greater flexibility and accept tubes with diameters varying over a wider range although at the cost of increased complexity. To some extent, they also cater for oblong cross-section tubes, although the risk of distortion mentioned about is not eliminated.
Another requirement of many users of such devices is to be able to attach the bike to the bike rack simply and very quickly. Most prior art devices require a large number of manipulations. It follows that the fixing of the bike to the bike rack is often complicated and time-consuming.
Finally, the fixing device must offer the user an acceptable level of security against theft, when the bike is fixed to the bike rack. This means that a thief must not be able to remove the bike from its support simply and quickly and without using special tools: hacksaw, bolt-cutters, etc.
An object of the invention is to overcome the drawbacks of the prior art devices and at the same time to meet the requirements as stated above.